function documentText(word, bottom = 30) {
    var style = document.createElement('style')
    style.innerHTML = `.docBtn{
        position: fixed;
        right: 30px;
        bottom: ${bottom}px;
        width: 54px;
        height: 54px;
        line-height: 54px;
        z-index:99;
        text-align: center;
        border-radius: 40px;
        background-color: rgba(0, 0, 0, .3);
        color: #ffffff;
        font-size: 20px;
    }`;
    var div = document.createElement('div')
    div.className = 'docBtn'
    div.innerHTML = '<i class="fa fa-file-word-o" aria-hidden="true"></i>';
    document.head.appendChild(style)
    document.body.appendChild(div)
    div.onclick = function () {
        layer.open({
            type: 1
            , title: "需求说明" //不显示标题栏
            , closeBtn: false
            // , area: 'auto;'
            // , maxHeight: '400px'
            , shade: 0
            , id: 'documentText' //设定一个id，防止重复弹出
            , btn: ['知道了', '我擦']
            , btnAlign: 'c'
            , moveType: 1 //拖拽模式，0或者1
            , content: word
            , success: function () {
            }
        });
    }
}